Application that crashed: plasma-desktop
Version of the application: 0.3
KDE Version: 4.3.1 (KDE 4.3.1)
Qt Version: 4.5.2
Operating System: Linux 2.6.30-1-amd64 x86_64

What I was doing when the application crashed:
I'm just switch the workspace (desktop) from one to another. Screen was blank and black, only cursor. In some seconds Crash Reporting Assistant started.

 -- Backtrace:
Application: Plasma Workspace (kdeinit4), signal: Segmentation fault
[Current thread is 1 (Thread 0x7f5ad63bf750 (LWP 3095))]

Thread 2 (Thread 0x7f5ab807e950 (LWP 3098)):
#0  0x00007f5ad2c36b89 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007f5ad5ef3469 in QWaitCondition::wait(QMutex*, unsigned long) () from /usr/lib/libQtCore.so.4
#2  0x00007f5ad22f1024 in ?? () from /usr/lib/libQtNetwork.so.4
#3  0x00007f5ad5ef2475 in ?? () from /usr/lib/libQtCore.so.4
#4  0x00007f5ad2c32f9a in start_thread () from /lib/libpthread.so.0
#5  0x00007f5ad37f956d in clone () from /lib/libc.so.6
#6  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f5ad63bf750 (LWP 3095)):
[KCrash Handler]
#5  0x00007f5ad44f4374 in QGraphicsItem::isWidget() const () from /usr/lib/libQtGui.so.4
#6  0x00007f5ad44f6a99 in QGraphicsItem::isWindow() const () from /usr/lib/libQtGui.so.4
#7  0x00007f5ad452ce39 in QGraphicsScene::event(QEvent*) () from /usr/lib/libQtGui.so.4
#8  0x00007f5ad3f6380d in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#9  0x00007f5ad3f6b86a in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#10 0x00007f5ad4bbd43b in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#11 0x00007f5ad5fd851c in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#12 0x00007f5ad453d2c6 in QGraphicsView::viewportEvent(QEvent*) () from /usr/lib/libQtGui.so.4
#13 0x00007f5ad5fd7838 in QCoreApplicationPrivate::sendThroughObjectEventFilters(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#14 0x00007f5ad3f637dc in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#15 0x00007f5ad3f6b86a in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#16 0x00007f5ad4bbd43b in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#17 0x00007f5ad5fd851c in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#18 0x00007f5ad3fb3cba in QWidget::event(QEvent*) () from /usr/lib/libQtGui.so.4
#19 0x00007f5ad431ccdb in QFrame::event(QEvent*) () from /usr/lib/libQtGui.so.4
#20 0x00007f5ad43acae9 in QAbstractScrollArea::event(QEvent*) () from /usr/lib/libQtGui.so.4
#21 0x00007f5ad3f6380d in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#22 0x00007f5ad3f6b86a in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#23 0x00007f5ad4bbd43b in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#24 0x00007f5ad5fd851c in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#25 0x00007f5ad3f6a3e5 in QApplication::setActiveWindow(QWidget*) () from /usr/lib/libQtGui.so.4
#26 0x00007f5ad3fd2ec1 in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib/libQtGui.so.4
#27 0x00007f5ad3ffae9c in ?? () from /usr/lib/libQtGui.so.4
#28 0x00007f5ad2e8086a in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#29 0x00007f5ad2e83eb8 in ?? () from /usr/lib/libglib-2.0.so.0
#30 0x00007f5ad2e8406c in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#31 0x00007f5ad6000bff in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#32 0x00007f5ad3ffa64f in ?? () from /usr/lib/libQtGui.so.4
#33 0x00007f5ad5fd6de2 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#34 0x00007f5ad5fd71b4 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#35 0x00007f5ad5fd9424 in QCoreApplication::exec() () from /usr/lib/libQtCore.so.4
#36 0x00007f5acb17926b in kdemain () from /usr/lib/libkdeinit4_plasma-desktop.so
#37 0x0000000000407264 in _start ()

Reported using DrKonqi